Ensete homblei

Ensete homblei

Ensete homblei (J. Bequaert ex E. A. J. De Wildeman, Ann. Mus. Colon. Marseille ser. 2, 10: 332 (1912) and Les Bananiers : 51 (1913)) E. E. Cheesman, Kew Bulletin 2 (2): 103 (1947) and R. E. D. Baker & N. W. Simmonds, Kew Bulletin 8 (3): 405 (1953).

Accepted name Ensete homblei (J. Bequaert ex E. A. J. De Wildeman) E. E. Cheesman, Kew Bulletin 2 (2): 103 (1947) and R. E. D. Baker & N. W. Simmonds, Kew Bulletin 8 (3): 405 (1953).

Synonyms Musa homblei J. Bequaert ex E. A. J. De Wildeman, Ann. Mus. Colon. Marseille ser. 2, 10: 332 (1912) and Les Bananiers : 51 (1913).

Authorities The source for the accepted name and synonym is Cheesman 1947a and Baker & Simmonds 1953.

Distribution A restricted area in the southern part of the Democratic Republic of Congo and neighbouring northern Zambia. (Possibly S.W. Tanzania).

Description A tiny species [in Ensete terms], 0.8 - 1.1 m. tall with small leaves and more canna-like than banana-like in general aspect. Pseudostem slightly swollen at the base, often (but not invariably) with 1 - 4 young corms around the mother-corm either as the result of spontaneous suckering or colonial germination of seeds. Leaf sheaths clasping mid-trunk half-way around the stem, the higher sheaths less clasping and leaves passing into bracts on the peduncle. Leaves (12 cm.) shorter than the sheaths, grey-glaucous, oblong-lanceolate, with elongated apices. Lamina halves turned upwards, forming a gutter, and midribs underdeveloped, upper half almost invisible, abruptly broadening towards the base and merging into the sheath. No petiole, but long sheath clasping around the stem for ca. 20 cm. or about 2/3 of its length. Peduncle short and erect, inflorescence subhorizontal, dense and small. Bracts almost reduced to sheaths, ending in a kind of pointed lamina, numerous, persistent, covering the fruits. Basal flowers female. Hermaphrodite flowers biseriate. Male flowers monoseriate, perianth 3-lobed, encompassing the shorter, free tepal which is 3 - toothed, its middle tooth long and mucronate; 5 stamens. Pollen small (120 µ; cf. pollen of E. ventricosum, which is 140 - 150 µ.). Fruits small (24 x 40 mm.), subpyriform, constricted at the base, apex rounded with a short point in the middle and an indistinct pedicel, glabrous, waxy and blackish, with scanty, pale-yellow, dry and bitter pulp. Seeds numerous, ovoid, angular, shining black, small (5 - 6 mm. high x 6 - 8 mm. in diameter). The plants found (invariably?) growing on termite mounts in wooded savannahs or dry grassland, dying down to a perennating, scale-covered corm as an ecological adaptation to unfavourable dry seasons and bush fires.
(De Wildeman 1912, Fawcett 1913, Milne-Redhead 1952, Baker & Simmonds 1953).

References Aluka, Baker & Simmonds 1953: 408, Champion 1967, Cheesman 1947a, De Wildeman 1912: 332, Fawcett 1913: 277-278, Lebrun & Stork 1995, Lock 1993, Milne-Redhead 1950: 150, Simmonds 1960, White & Angus 1962.

Comments Cheesman created Ensete homblei as a new combination (number 22 out of 25) in a brief note in his 1947 paper reviving the genus Ensete. Cheesman revived one and created 24 Ensete species in that paper but acknowledged that field study might reveal synonymy. Thus far the status of E. homblei has not been challenged.
This is a highly intriguing little species for a number of reasons.

According to Cheesman (1947 a) "This species is exceptional in the size of its seeds, which are the smallest I have seen in the genus, only 6 - 8 mm. in diameter. In shape and structure, however, they conform to the general Ensete pattern, and from De Wildeman's description there can be no doubt about the affinities of the species".

According to Milne-Redhead (1950: 2-3) it was "J. Bequaert [who] collected the plant at the beginning of the dry season in 1912, when he got it in fruit. A detailed description made in the field by him was published by De Wildeman (l.c. 332-336). The flowers, however, have not until now been described. [ ] The deciduous perennial habit, the presence of suckers are both anomalous characters, no doubt associated with the abnormal (for Ensete) conditions of the habitat in which the species thrives. [ ] In E. Homblei the flowers subtended by each bract are arranged in but a single series, as against two in [other] Ensete [species]. Whilst this may be just another example of the reduction in size that has produced E. Homblei, there is another character which cannot be so explained. K. Schumann (Das Pflanzenreich IV. 45, Musaceae, 6: 1900) mentions that Musa Ensete J. F. Gmel. and its allies (species now placed in Ensete by Cheesman) lack the free blades of the two inner anterior tepals. These are present, however, in E. Homblei, conspicuously in the male flowers (fig. 4), whilst in the female flowers they are smaller and remain adhering by their edges to the lobes of the outer perianth".

Whether the species really does spontaneously sucker in nature is still a matter for conjecture. Baker & Simmonds (1953: 408), are of the opinion that "the apparent tendency to suckering and therefore to a perennial habit which has been noted by several authors is probably due to aggregated germination and hence to growth of seedlings in clumps, each individual seedling being truly monocarpic even if it grows up and dies down several times before flowering".

E. homblei is normally (invariably?) associated with termite mounds, an interesting phenomenon requiring an explanation. This may simply be due to locally favourable soil conditions as the result of the termites excavating activities. However, those with local knowledge of the plant speculate that the association may be due to protection afforded by the termites against root-knot nematodes. In addition, the termites may in some way also protect against infestation by the banana borer weevil (Cosmopolites sordidus). As a small plant of drought-prone areas E. homblei may be less able to tolerate borer infestation than the more robust E. gilletii although that species too is regularly infested.

It can be said for E. homblei as for E. gilletii that "much more information is needed on [the] biology and life cycle" of this fascinating little species (Baker & Simmonds 1953).

Type: Homblé no. 671 (in Herb. Brux.) (Baker & Simmonds 1953: 408).

Images:

There are six images of Ensete homblei.
There is one external image of Ensete homblei at the Aluka website http://www.aluka.org

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last updated 24/11/2007

Accepted name	Ensete homblei (J. Bequaert ex E. A. J. De Wildeman) E. E. Cheesman, Kew Bulletin 2 (2): 103 (1947) and R. E. D. Baker & N. W. Simmonds, Kew Bulletin 8 (3): 405 (1953).
Synonyms	Musa homblei J. Bequaert ex E. A. J. De Wildeman, Ann. Mus. Colon. Marseille ser. 2, 10: 332 (1912) and Les Bananiers : 51 (1913).
Authorities	The source for the accepted name and synonym is Cheesman 1947a and Baker & Simmonds 1953.
Distribution	A restricted area in the southern part of the Democratic Republic of Congo and neighbouring northern Zambia. (Possibly S.W. Tanzania).
Description	A tiny species [in Ensete terms], 0.8 - 1.1 m. tall with small leaves and more canna-like than banana-like in general aspect. Pseudostem slightly swollen at the base, often (but not invariably) with 1 - 4 young corms around the mother-corm either as the result of spontaneous suckering or colonial germination of seeds. Leaf sheaths clasping mid-trunk half-way around the stem, the higher sheaths less clasping and leaves passing into bracts on the peduncle. Leaves (12 cm.) shorter than the sheaths, grey-glaucous, oblong-lanceolate, with elongated apices. Lamina halves turned upwards, forming a gutter, and midribs underdeveloped, upper half almost invisible, abruptly broadening towards the base and merging into the sheath. No petiole, but long sheath clasping around the stem for ca. 20 cm. or about 2/3 of its length. Peduncle short and erect, inflorescence subhorizontal, dense and small. Bracts almost reduced to sheaths, ending in a kind of pointed lamina, numerous, persistent, covering the fruits. Basal flowers female. Hermaphrodite flowers biseriate. Male flowers monoseriate, perianth 3-lobed, encompassing the shorter, free tepal which is 3 - toothed, its middle tooth long and mucronate; 5 stamens. Pollen small (120 µ; cf. pollen of E. ventricosum, which is 140 - 150 µ.). Fruits small (24 x 40 mm.), subpyriform, constricted at the base, apex rounded with a short point in the middle and an indistinct pedicel, glabrous, waxy and blackish, with scanty, pale-yellow, dry and bitter pulp. Seeds numerous, ovoid, angular, shining black, small (5 - 6 mm. high x 6 - 8 mm. in diameter). The plants found (invariably?) growing on termite mounts in wooded savannahs or dry grassland, dying down to a perennating, scale-covered corm as an ecological adaptation to unfavourable dry seasons and bush fires. (De Wildeman 1912, Fawcett 1913, Milne-Redhead 1952, Baker & Simmonds 1953).
References	Aluka, Baker & Simmonds 1953: 408, Champion 1967, Cheesman 1947a, De Wildeman 1912: 332, Fawcett 1913: 277-278, Lebrun & Stork 1995, Lock 1993, Milne-Redhead 1950: 150, Simmonds 1960, White & Angus 1962.
Comments	Cheesman created Ensete homblei as a new combination (number 22 out of 25) in a brief note in his 1947 paper reviving the genus Ensete. Cheesman revived one and created 24 Ensete species in that paper but acknowledged that field study might reveal synonymy. Thus far the status of E. homblei has not been challenged. This is a highly intriguing little species for a number of reasons. According to Cheesman (1947 a) "This species is exceptional in the size of its seeds, which are the smallest I have seen in the genus, only 6 - 8 mm. in diameter. In shape and structure, however, they conform to the general Ensete pattern, and from De Wildeman's description there can be no doubt about the affinities of the species". According to Milne-Redhead (1950: 2-3) it was "J. Bequaert [who] collected the plant at the beginning of the dry season in 1912, when he got it in fruit. A detailed description made in the field by him was published by De Wildeman (l.c. 332-336). The flowers, however, have not until now been described. [ ] The deciduous perennial habit, the presence of suckers are both anomalous characters, no doubt associated with the abnormal (for Ensete) conditions of the habitat in which the species thrives. [ ] In E. Homblei the flowers subtended by each bract are arranged in but a single series, as against two in [other] Ensete [species]. Whilst this may be just another example of the reduction in size that has produced E. Homblei, there is another character which cannot be so explained. K. Schumann (Das Pflanzenreich IV. 45, Musaceae, 6: 1900) mentions that Musa Ensete J. F. Gmel. and its allies (species now placed in Ensete by Cheesman) lack the free blades of the two inner anterior tepals. These are present, however, in E. Homblei, conspicuously in the male flowers (fig. 4), whilst in the female flowers they are smaller and remain adhering by their edges to the lobes of the outer perianth". Whether the species really does spontaneously sucker in nature is still a matter for conjecture. Baker & Simmonds (1953: 408), are of the opinion that "the apparent tendency to suckering and therefore to a perennial habit which has been noted by several authors is probably due to aggregated germination and hence to growth of seedlings in clumps, each individual seedling being truly monocarpic even if it grows up and dies down several times before flowering". E. homblei is normally (invariably?) associated with termite mounds, an interesting phenomenon requiring an explanation. This may simply be due to locally favourable soil conditions as the result of the termites excavating activities. However, those with local knowledge of the plant speculate that the association may be due to protection afforded by the termites against root-knot nematodes. In addition, the termites may in some way also protect against infestation by the banana borer weevil (Cosmopolites sordidus). As a small plant of drought-prone areas E. homblei may be less able to tolerate borer infestation than the more robust E. gilletii although that species too is regularly infested. It can be said for E. homblei as for E. gilletii that "much more information is needed on [the] biology and life cycle" of this fascinating little species (Baker & Simmonds 1953). Type: Homblé no. 671 (in Herb. Brux.) (Baker & Simmonds 1953: 408). Images: There are six images of Ensete homblei. There is one external image of Ensete homblei at the Aluka website http://www.aluka.org